This application relates to a universal filter insert for use in a wide variety of water purifiers. Filter inserts for a water purifier are traditionally made for a specific water purifier. Some manufacturers even require different filter inserts for different models of their water purifiers. This complicates manufacturing, shipping and storage, requires multiple production runs, and increases prices. Therefore, what is needed is a universal filter insert for a water purifier, which will adapt the filter insert for use with a wide variety of water purifiers of varying sizes and shapes.
U.S. Pat. No. 4,666,600 issuing to Hankammer on May 19, 1987 discloses an insert for a water purifier with a cup portion connected thereto. The insert has at least one guide tube, and preferably multiple guide tubes assembled in concentric relationship with each other, with a filter means provided in the inner guide tube.
U.S. Pat. No. 4,764,274 issuing to Miller on Aug. 16, 1988, discloses a replaceable water filter unit utilizing activated charcoal particles sandwiched between a pair of felt pads.
U.S. Pat. No. 4,895,648 issuing to Hankammer on Jan. 23, 1990, discloses a filter cover for a purification insert in a water treatment device. Slots are provided on the conical surface portion, and at least one vent opening is provided in the middle of a raised connecting portion, and an adjustable pointer is rotatably connected to a hollow tube.
U.S. Pat. No. 4,306,971 issuing to Hankammer on Dec. 22, 1981, discloses a water purifying apparatus having a cup shaped insert with screen like closure members at the upper and lower ends, and a ventilation tube projects upward above the vertical height of the funnel-shaped member. A granular purifying agent is placed within the cup-shaped insert.
U.S. Pat. No. 5,637,214 issuing to Kahana on Jun. 10, 1997, discloses a water filter assembly having a filter bag of porous material housed in a filter housing. The filter housing has a plurality of elongated slots in the lower end of the filter housing, with slot-like apertures in the filter housing lid. The water filter assembly is adapted to be received in a water pitcher.
U.S. Pat. No. 3,780,867 issuing to Zirlis on Dec. 25, 1973 discloses a two stage water purification cartridge disposed within a housing. Water circulates from an inlet port in the cap through the outermost sleeve to the interior of the cartridge, and then out through an outlet port in the cap.
U. S. Pat. No. 3,705,651 issuing to Klein on Dec. 12, 1972 discloses a disposable filter unit for potable water, having an inner core filled with activated carbon and surrounded by porous material impregnated with diatomaceous earth.
U.S. Pat. No. 4,212,743 issuing to Van Meter et al. On Jul. 15, 1980 discloses a filter cartridge for water filters. Partitions within the cartridge define an elongated tortuous water flow path between the inlet and the outlet.
U.S. Pat. No. 3,747,767 issuing to Hankammer on Jul. 24, 1973, discloses a water treatment device formed of a funnel shaped part with an elongated tubular shaped shell connected to the funnel shaped part. The funnel shaped part is elastic and deforms when the shell is inserted to provide a seal-type engagement. Removable covers are provided for opposite ends of the shell.
U.S. Pat. No. 5,225,078 issuing to Polasky et al. On Jul. 6, 1993, discloses a pour-through pitcher assembly having a filter element with a thin annular disk of activated carbon, and a peripheral annular seal element.
U.S. design patent 323,874 issuing to Hirman et al on Feb. 11, 1992 discloses a removable filter element.